Sources say Juarez was frisked before he was led without handcuffs into a room with three people who would all be shot shortly after.

Armando Juarez mugshot (Dallas County Jail)

Officers Rogelio Santander and Crystal Almeida arrived at the North Dallas Home Depot Tuesday afternoon after Juarez was stopped for suspicious activity by an off-duty Dallas officer working security at the store and during a background check found that “a felony warrant hit came back for the suspect.”

“As the off-duty officer, you call uniformed patrol officer to take the prisoner to jail and they’ll usually send two like they did,” said retired Dallas Police officer Rich Emberlin.

Emberlin once worked off-duty at the same Home Depot and says the suspect should have been handcuffed.

“You do sometimes have be a little more forceful and detain them and say, ‘I’m going to put some handcuffs on you’,” said Emberlin.

But sources say Juarez was not cuffed and the off-duty officer failed to detect the handgun in his pocket during a pat-down.

Sources say the suspect fired nine rounds in a second when he was told he was going to jail.